Incandescent lamps (light bulbs) create light by running electricity through a thin filament, thereby heating the filament to a very high temperature so that it glows and produces visible light. A broad range of visible frequencies are naturally produced, yielding a pleasing warm yellow or white color quality. The incandescing process, however, is highly inefficient, as over 98% of its energy input is emitted as heat (98% dari energi hilang sebagai panas –> sangat tidak efisien)
A standard 100 watt 120 VAC light bulb produces about 1700 lumens, about 17 lumens per watt. Incandescent lamps are relatively inexpensive to produce. The typical lifespan of a mains incandescent lamp is around 1,000 hours (Daya tahan lampu sekitar 1000 jam)
Fluorescent lamps (light bulbs) work by passing electricity through mercury vapor, which in turn produces ultraviolet light. The ultraviolet light is then absorbed by a phosphor coating inside the lamp, causing it to glow, or fluoresce. While the heat generated by fluorescent lamps is much less than its incandescent counterpart, energy is still lost in generating the ultraviolet light and converting this light into visible light (meskipun panas yang dihasilkan lebih sedikit dari lampu pijar tradisional, tetapi masih ada energi yang hilang karena sinar UV yang dirubah menjadi cahaya). If the lamp breaks exposure to mercury can occur (Jika lampu pecah,ada bahaya mercuri). Lifetime varies from 1,200 hours to 20,000 hours (Daya tahan lampu 1,200-20,000 jam) for compact fluorescent lamps.
Keterangan lebih lanjut :